Realistic Trap Configuration Scheme with Fabrication Processes in Consideration for the Simulations of AlGaN/GaN MIS-HEMT Devices

AlGaN/GaN metal-insulator-semiconductor high-electron mobility transistors (MIS-HEMTs) have become a promising candidate for use in efficient power conversion applications. However, under the practical HEMT device fabrication conditions, additional interfacial trap states generated by the fabrication process will strongly affect the device performance of the MIS-HEMTs. Such influences have so far been considered and modeled only at specific fabrication conditions. At the device design and simulation stage with various different processes, there lacks a simple and versatile scheme for a quick design evaluation. In this paper, we report a scheme of realistic trap configuration with fabrication process taken in consideration. This configuration is able to bring the simulation outcome closer to the actual device performance, which is largely affected by the interfacial trap conditions within various locations. The formation of the proposed configuration scheme started from the raw AlGaN/GaN wafer with transmission-line measurement patterns for 2-D electron gas charge density, followed by benchmarking the normally ON and normally OFF MIS-HEMTs devices made through actual fabrication processes. The relationship between interfacial trap density and fabrication processes was then identified. Finally, a test case on AlGaN/GaN inverter configuration involving both normally ON and normally OFF devices was used to demonstrate the effectiveness of the proposed scheme.